


Stolen Fishes & Eggcellent Wishes

by SuccubustyKisses



Series: Monsterfucker Bingo [1]
Category: Voltron: Legendary Defender
Genre: Alternate Universe - Mermaid AU, Bottom Shiro, M/M, Oviposition, Tentacle Dick, human shiro, merman Keith, porn with little plot
Language: English
Status: Completed
Published: 2019-02-21
Updated: 2019-02-21
Packaged: 2019-11-01 15:29:57
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,075
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17869865
Author URL: https://archiveofourown.org/users/SuccubustyKisses/pseuds/SuccubustyKisses
Summary: “Keith, you know if I do something you don’t like all you have to do is say so and I will never do it again. I would never pressure you into anything.” Shiro lets out the same sentence he's said many times before in many different ways.The pufferfish drops into its new tank and Keith turns to Shiro, confusion knitting his brow as he holds the plastic bag to his chest.  “I know that, Shiro. Why would you think you did something wrong?”“Because every time I try to get intimate with you, you run away like I lit your ass on fire.” Shiro tries to not sound dejected, but he knows he fails as he looks up into Keith’s guilty face.Sighing loudly Keith steps down from the stool. “I know, Shiro. I promise, it will all make sense soon. Just… please bear with me a little bit longer.”





	Stolen Fishes & Eggcellent Wishes

**Author's Note:**

> Part one of my Monster Fucker Bingo is off with a real bang! The request was sheith mermaid au and who was I to resist trying out something new and adding in some fun kinks?

Dates to the mall are a common thing for Shiro, even before he started actually dating his long time friend and current boyfriend Keith they would come to the mall almost every time they hung out. It wasn’t for shopping though, but because the mall had the best pet store in town. A huge place filled to the brim with pens, cages, and tanks. All sorts of animals graced the inside of Olia's Pet Den. 

Truthfully it was where Shiro had first met Keith, a young boy standing on his own in front of the fish tanks, frowning up at the fish inside with no parental supervision in sight. Shiro seeing a boy close to his age had lunged at the opportunity to make a friend and waltzed right up to him holding his hand out for a shake. Keith hadn't even looked away from him. Just said the fish he was frowning at was sad. The next thing Shiro knows is he was distracting the adults while the strange boy stole a fish in a McDonald’s cup and took off outside of the mall.

That fish was still alive, Shiro always searches for it in Keith’s tank in his kitchen. According to Keith the fish likes to watch people eat. 

So, Keith and Shiro have always come to the mall, even after confessing to each other they still come to Olia's. The only difference is now they hold hands as they move slowly through the fish section.

Keith stops at the saltwater tanks, looking around at the wide array of exotic fish, his mouth opening in a soft clicking noise Shiro has come to enjoy. “So, what are the fish saying today?” Shiro asks with a smile, wrapping his arms around Keith’s shoulders and brushing his cheek in his hair. 

Keith pauses, then clicks some more, adorable little squeaks coming out from time to time drawing weird looks from other shoppers but just making Shiro smile. Keith really was adorable. They shift over a little bit and Keith tiptoes to look into a higher tank housing a dark colored fish that quickly swims to the back as if looking for a place to hide. “This puffer fish is scared and stressed, that could cause major health complications… I'm bringing him home.”

Shiro chuckles, looking at the hefty sum for the fish, nothing Keith can’t afford. “Whatever you say, dear. Shall I go pick up our lunch while you purchase the fish?”

Nodding without a word Keith continues to stare at the tank, pressing closer and clicking softly. Shiro places a kiss on his temple and steps back, turning to head for the food court knowing Keith won’t wait long once the fish is placed in it 'plastic prison of transport'.

* * *

Smiling up at Keith's house Shiro parks his car, unsurprised when his boyfriend lets out a cute trill down at the bag in his hands before quickly climbing out and hurrying towards the door. Chuckling to himself Shiro turns off the car and takes his time walking towards the giant three story beach house. 

As he walks in the door Shiro listens to the white noise of the room. The sounds of water filters pouring waterfalls of fresh water into tanks fill the entire house in a soothing trickle. He makes his way through the house, watching as some fish swim away from him and others swim to greet him. Passing fish tank after fish tank Shiro moves up the steps, listening quietly until he hears the telltale clicking. 

_Found him._

Shiro veers to the left, walking down the hallway. He stops at an open door, peeking in to find Keith crouched down in front of one of his tanks, looking back and forth from the tank to the fish in his grasps. A low whistle escapes his lips followed by a few clicks, then Keith stands and turns to Shiro. “He doesn't like this one either.”

“Too full?” Shiro asks, stepping aside to let Keith pass. Keith nods with a pout. “How about the one in the second guest room? That one you just had deep cleaned a few months back so most of the fish were moved?”

Keith's eyes light up, his pupils growing to take up most of the violet color as a bright smile fills his face. “Shiro you're a genius!” tiptoeing up Keith presses a quick kiss to Shiro’s lips before he rushes off down the hall to the suggested tank. 

Shiro moves more slowly, taking his time heading for the room. He steps inside the doorway giving a proud smile as Keith stands on a fold out stool lowering the pufferfish’s plastic prison to float on the water in his suggested tank. “So he likes it then?”

“He does.” Keith turns, still on the stool to smile softly at Shiro, melting his heart. “You always know just what to do for my fish.” 

Stepping forward Shiro stops just in front of Keith smirking up at him. “Well, I did learn from the best.”

“Mmmm.” Keith leans forward, pressing a kiss to Shiro's lips. “You flatter me.”

Shiro closes the distance between them again, pressing a kiss onto his boyfriend’s lips, and then another. The kisses grow deeper, tongues weaving together in their own private dance as Keith presses a hand to Shiro’s chest. He pushes him back, stepping forward as he goes, walking them backwards until Shiro’s knees hit the bed and he sits hard on the soft surface. 

Keith climbs up into Shiro's lap, wrapping his arms around his neck and burying his fingers in his hair. Shiro groans into the kiss, his hands moving to Keith’s waist, sliding down to grip tightly at his hips. His fingers shift under Keith’s shirt, running along the flesh, the hot and cold contrast making Keith shudder against him. 

They pull back, foreheads pressed together as Shiro’s hands move slowly up Keith’s back, pulling him closer to his chest. Shiro lets out a pleased groan as Keith rolls his hips forward, grinding against Shiro’s rapidly hardening cock. His fingers dig into Keith's back, a moan filling the air between them as their lips crash back together. Teeth and tongue war for dominance as hips grind together, gasps and moans filling the air around them as Shiro moves his hands back down Keith's sides. His fingers dip into the waistband of Keith's pants.

Keith jumps off his lap, leaving Shiro looking wide eyed up at him, hands held out wide. “I better put the pufferfish in his new home so we can eat!” He moves quickly towards the tank leaving Shiro sitting alone in the bed with a rock hard dick and a loud sigh. 

“Keith, you know if I do something you don’t like all you have to do is say so and I will never do it again. I would never pressure you into anything.” Shiro lets out the same sentence he's said many times before in many different ways.

The pufferfish drops into its new tank and Keith turns to Shiro, confusion knitting his brow as he holds the plastic bag to his chest. “I know that, Shiro. Why would you think you did something wrong?”

“Because every time I try to get intimate with you, you run away like I lit your ass on fire.” Shiro tries to not sound dejected, but he knows he fails as he looks up into Keith’s guilty face. 

Sighing loudly Keith steps down from the stool. “I know, Shiro. I promise, it will all make sense soon. Just… please bear with me a little bit longer.”

Keith steps forward, pressing a kiss to the corner of Shiro's lips. Sighing loudly Shiro gives him a half hearted smile. “So, I guess we should go eat then?”

* * *

Climbing out of the car Shiro yawns loudly into the air looking up at the familiar three story beach house. 

_The worst part of not having sex is the sleep I lose driving home and back again._

Stifling another yawn he steps up to the door, not even bothering to knock, he just pulls out his key and lets himself inside. “Keith? I'm here.”

All that answers him is the sound of water trickling down from it's filters. Shaking his head Shiro moves through the house, stopping to talk to the blue and black betta swimming excitedly at the front of its tank waiting for him. “Hey there, Kosmo. How are ya old man? Have you seen your human provider?”

The betta frills its gills at him, swimming in a few circles before swimming over to the edge of the tank. Shiro's eyes follow him, settling on the note taped to the glass. “Oh! Thank you Kosmo. Good boy.” 

Swiping the note he reads the words directing him to the private beach in the back of the house. Shaking his head Shiro sets the note on the kitchen counter and heads out the door. He follows the steps down onto the golden sand, his eyes drift from one side to the other, searching for his boyfriend. “Keith?”

A soft splash draws his eyes to the ocean, the waves small and subtle in the growing morning light. He focuses his sight on an abnormal ripple, eyes widening when a long tail flips out of it. It's scales are nearly metallic, glittering in the sunlight in an ombre of red, pink, purple, and black. A large frilled fin runs down the back of it, shifting in the waves as it disappears once again under the water. Just as the last serrated edge of the tail disappears under the water a head emerges, dark hair pushed back behind multiple pointed ears, almost like fins, scales running down the side of his face and neck and over his shoulders.

“Keith?!” Shiro stares, eyes wide and mouth opening and closing as he looks for something, anything to say. His eyes follow the movement as Keith swims closer, pressing his chest into a large rock and propping his arms up on them. “Holy shit you look amazing. I mean, you always look amazing, but now you look out of this world. I mean, god damn it. This explains so much.”

Nervousness radiates off Keith in waves as he turns to look at Shiro. “So… this is my secret.”

“It good. Good. I mean… great… fuck. It’s a good secret. A great one… it's _gorgeous_.” Shiro fumbles over his words, eyes trailing over what he can see of Keith’s body. 

Keith's cheeks tint an adorable shade of violet as he watches Shiro. He pushes up on the rock more, watching Shiro’s eyes adjust to the freshly bared skin. “Do you… want to come get a closer look?”

“ _Yeah._ Yes, yes I do. Very much so.” Kicking off his shoes at the same time as pulling off his shirt Shiro moves forward, stepping into the cooling morning waves. He pushes through the soft press of the tide until the waves are hitting halfway up his chest. 

A fang filled smile takes up Keith’s face before he slides down off the rock. Shiro watches pale flesh and glittering scales swim towards him, looping around his legs under the water. His fingers run across Shiro’s skin making him shiver before he emerges slowly from the water directly in front of him. “Hey.”

“Hey. Hi. Yeah, hello.” Shiro's fingers itch to touch as his eyes take in Keith’s beauty in front of him. Keith's smile turns coy as he reaches out, clawed fingers running down Shiro’s arms to grip his wrist and pull his hands onto his own waist.

“You can touch me, Shiro.” Keith’s words were spoken smugly, but his face betrays his nervousness. 

Taking a deep breath Shiro lets his fingers slide along Keith's sides, his skin is smooth, his scales barely feeling like bumps as he runs across them, but pulling and hitching up if he moves his hand opposite their flow. Hands wander down Keith’s chest, feeling along his tail as he lifts it up. Shiro stops for a moment to marvel at his hand through the transparent opalescence of Keith’s back fin before moving down further. 

Breath hitching at the soft, intimate touches Keith tries to move to make each touch easier for Shiro. He watches Shiro's face as his fingers trace his scales, sending tingles of pleasure through his body. Keith tries to breathe slowly, taking deep breaths to keep himself as calm as he can. 

Shiro’s hands returned to his chest, moving up his scales and wrapping fingers slowly around his neck. Keith presses into the touch, looking up at shiro with wide eyes, his pupils slitted like a cats. “Can I kiss you?”

Keith lets out a soft moan, a series of clicks mingling in with it as he closes his eyes. “Gods, yes. Please.” 

Shiro pulls lightly on Keith’s cupped chin, tugging him forward to press their lips together. The kiss is instantly hot and heavy. Gasps of pleasure mingling between their lips as their tongues move together. They press closer together, Keith digging his claws lightly into Shiro’s back as Shiro wraps his arms around his waist and yanks him in tight, hip to hip. 

Keith's tail wraps around Shiro’s waist, pulling him in hard and grinding their hips together painfully. Shiro gasps, pulling back as a hot slickness writhes against his stomach. 

Looking down Shiro’s eyes widen, his hand moving to touch the slithering appendage coming out of a slit in the front of Keith’s tail just between his hips. He grasps it lightly and Keith bucks, the tendril wrapping around Shiro's wrist and pulling him to move it. Shiro obliges and a squeak of noise echoes through the air around them. “So, this is why you always pulled away when we got intimate?”

Laughing breathily Keith snuggles into Shiro’s neck, sharp teeth grazing his shoulder. “It would be kinda hard to explain a tentacle dick to a human.”

Shiro laughs too, his hand moving down to the base and squeezing, feeling a hard pressure of something moving up along it. “I don’t think I would have minded.” He squeezes again, feeling something else hard pressing past his grip. “What is that I’m feeling.”

Keith’s deep blush returns. “That’s… well… that’s my eggs.”

“Your… eggs?”

Keith laughs nervously. “You see, male Merpeople carry eggs, during sex they inject them into the female who fertilizes them inside of her and carries them to a safe term before they lay them in a safe place before hatching.”

“Huh… so would I have fish babies if you-“ Shiro looks intrigued, squeezing again in wonder.

Laughter bursts out of Keith. “No, no. Humans and Merpeople can’t reproduce together unless the Mer gives up their tail and becomes a mortal human or the human becomes a mer.”

“Alright…” Shiro's hand moves along the length, feeling the eggs moving gently inside with his touch. His fingers poke at the tapered tip, thumb pressing into it. “Keith I want you to fuck me. Like, yesterday.”

“Excuse me?” Keith’s ears seem to perk out reminding Shiro of Kosmo's puffed out fins. 

“Put your eggs in me Keith.” Not having to be told _that_ twice Keith's lips press into Shiro’s in another deep kiss. His fangs graze gently against Shiro’s bottom lip as his hands wander, running down Shiro's chest, feeling every dip of muscle, every upraised scar. When his hands reach Shiro's shorts they don’t even hesitate to stop, dipping into his shorts and gripping his ass with a tight squeeze. 

Pulling from the kiss Keith trails kisses to Shiro's jaw, then up to his ear as his hands push the offending shorts down and out of his way. “You wanna know a fun benefit of a male Mer's cock?” Taking Shiro's hand he places it on his writhing cock, letting out a pleased huff as the fingers grip it and slip along the bumped surface. “Waterproof self lubrication.”

Shiro pulls his hand up, looking at the sticky slick fluid slowly sliding down his fingers. It’s a pearlescent pink and purple. His tongue darts out to lick along one finger in curiosity, surprised to find the taste sweet. “God, Keith. You really are perfect.” 

Keith grins, running his hands along his own cock for a few pumps before reaching around Shiro and running his fingers along his crack. As he pressed gently on Shiro's puckered opening his mouth explored Shiro's skin, kissing down his neck, nipping at his collarbone and moving lower. 

Shiro moans, wrapping his arms around Keith’s head as Keith's tongue runs along his chest, swirling a nipple before nipping it. His finger presses carefully into his hole, moving carefully in and out. 

Continuing his path, Keith kisses his way down Shiro’s chest, his head submerging under the water and tongue darting out to run along Shiro's length. His mouth opens wide, sucking Shiro’s length down his throat with ease, having no problems breathing around it due to his gills. Shiro bucks forward, fingers lacing in Keith’s hair as the hot press of his tongue massages the underside of his cock. Keith pulls back slowly then bobs back down fast again, this time pressing a second finger in along with the first. 

Shiro keens, back bowing. Wherever Keith's slick moisture touched now tingles with warmth sending jolts of pleasure through his system. He bucks forward, practically fucking into Keith’s mouth as two fingers quickly become three. He knows the stretch should probably sting, or send a pain pleasure pull through him, instead he just feels hot unbridled pleasure making his dick twitch, so close to release. 

Keith stops, hands pulling out of his stretched hole to press into his back just above his ass. He pushes Shiro forward until his nose is crushed tight against Shiro's coarse pubic hairs. His tongue presses into it and he swallows around the length down his throat. Within seconds Shiro is twitching and releasing his salty seed down Keith’s waiting throat. Keith swallows it down eagerly, until Shiro is shaking and moaning with overstimulation, pulling himself back and away from Keith’s convulsing throat.

Shiro looks down into the water, mouth open to pant in the salty air as his eyes settle on Keith below him. The violet of Keith's eyes glow up from the water, his scales shimmering in the light with their own multicolored ethereal glow. Shiro's smile is lopsided as Keith slides back up out of the water, hands running up Shiro’s back and tail easily holding him up until the two are face to face. “Hey.”

Snorting a laugh, which held a squeaky undernote, Keith moves his hands to press to Shiro's chest. “Hi there.” Clawed fingers spread out on his chest, flashing the transparent webbing between them. “So, are you… still good with this?”

Shiro's hands move, one settling on Keith's hip and the other gripping his cock. The eggs within shifting at his grip. He can feel them press tightly together, the once slithering like movements of the appendage now slower, less malleable. “I have never been so good. I've wanted you for so long, Keith.”

“Fuck, Shiro.” A low rumble comes from Keith’s chest, vibrating the water around them as he pushes Shiro back until he's pressed into the rock Keith had leaned on before. “Turn around, please.”

After placing a soft kiss on Keith’s lips Shiro turns, wrapping his arms around the rock and jutting his ass out for show. Sharp teeth graze the globe of his ass before Keith moves his body up until his slick cock, coarse with eggs, slides along Shiro’s crack. 

Before Shiro can even react to the warm tingle along his flesh Keith is pressing the slightly opened, tapered tip of his cock into his opening. With every press another ridge of eggs pushes into him, making him gasp and moan out. The more he pushes the more full Shiro feels, a strange rolling sensation starting along his passage. “Haa- Shit, Keith I-“ something presses against his prostate and his back bows as he moans out loudly. 

Keith chuckles, resting his hands on the rock on either side of Shiro’s head, he leans down, making small, shallow thrusts. “You feel that, Shiro? My eggs are already starting to fill you up they just couldn’t wait to be inside you.” 

Keith's dick moves inside him, wiggling along the few eggs that had already escaped upon insertion. Shiro groans, burying his face in his arms as his hips buck forward against the rock. Keith chuckles, pulling back and pressing in again hard and fast. 

Shiro’s moans are loud and broken as Keith sets a pace, pushing the eggs he's already released further inside of him. With each thrust more eggs move into his cock and with every shift another pushes out of his opening. His gasps and moans have an underlying vibration that run through his body making his cock shake inside of Shiro.

“Hnnn- Shiro.” Keith presses in, kissing the back of Shiro’s neck. “I have dreamed about this since my first ovulation. I have wanted nothing more than to see my eggs fill you up.” 

A whimper escapes from Shiro's lips as he thrusts his ass back, fingers scraping for purchase on the rocks. His dick bobs in the air, pre dribbling down onto the rock below. “Keith, I can feel them inside me. You're filling me up.”

“Just- ah- little bit more. I'm almost there Shiro.” His forehead presses in between Shiro's sweaty shoulder blades, his thrusts becoming erratic as he chases his own release. “Gonn-haaa make both our dreams come true.”

Shiro opens his mouth to answer but all that comes out is a loud, broken moan as Keith jams his cock in hard, his hips smacking into Shiro’s ass. The massive release of eggs inside of him feels like something alive is slowly pressing itself up, further and further within his body, crashing together deep inside while Keith’s dick undulates within him as his body forces the eggs out. It's a constant press on his prostate at this point, making him writhe and groan. 

Keith reaches around to grip his dribbling cock, jerking it once, twice, three times before Shiro's cum is splashing onto the wet rock below him. Once milked dry Keith moves his hand to wrap lightly around Shiro’s waist, pulling him carefully, still buried deep within him, back down into the water. His dick still convulses, trying to release more eggs than he actually has, wanting to see Shiro swollen with his clutch. 

Shiro pants into the air, hand shifting to lay over his lower abdomen, unsurprised to find he can feel the bumps of the eggs within him. They stay there in the shallows of the water, Keith’s webbed hand held over Shiro’s for a few silent moments before Shiro finally looks down.

His stomach is slightly distended, bumps sticking out along his flesh, glowing a faint purple through his skin. “Hey Keith.”

Keith hums, a high pitch chirp of noise in Shiro’s shoulder. “yea?”

“How long are these going to be in me?” Shiro can feel the moment Keith’s body freezes up, the hard swallow that follows. “Keith?”

“Um…”

“Keith. How long am I going to have a bumpy glowing stomach?” Shiro pulls away, feeling Keith’s dick pull from his body, he turns resisting the urge to watch the appendage return to its hole inside Keith to stare at his face. “Keith?”

“I… don’t… actually know?”

“Keith I can’t walk around with your glowing unfertilized children within me!” Shiro looks on the verge of panic.

“Then don’t. Stay here with me. Move in with me, Shiro. With us. Kosmo would love to see you every day.” Keith looks determined up at him.

Letting out a loud sigh Shiro smiles down at him. “Fine. But I'm going inside now to take a shower, and you are going to go find out how long I’m going to be a human glow stick.” 

Keith grins, splashing up to wrap his arms around Shiro’s shoulder, his tail around his knees, and placing a deep, excited kiss to his lips. “I love you, Shiro.”

Before Shiro can answer Keith is pushing away, splashing down into the water. Shiro’s eyes follow the glow of his scales until they disappear from sight, then looks down at the glow of eggs within him. “I wonder how hard it is to become a Mermaid myself?”

**Author's Note:**

> I hope you enjoyed reading.
> 
> Find me on SuccubustyKisses on ao3 and pillowfort as well as SuccubustyKiss on twitter. 
> 
> The rest of the bingo fics will not be posted publicly until the card is complete, so this is just a teaser on what is still to come.


End file.
